As a resin binder for toners, an amorphous polyester has been conventionally frequently used, from the viewpoint of fixing ability and durability. However, development of a toner having even more improved fixing ability and durability has been required. Accordingly, in addition to the amorphous polyester, there has been proposed a toner containing a crystalline polyester itself having a releasing effect as a resin binder, from the viewpoint of improving fixing ability (see JP2001-222138 A and JP2004-61875 A).
On the other hand, with the increasing demands for on-demand printing, there has been required a toner and a developer which can meet the requirements of both high-quality image and high speed. To cope with deterioration of the developer due to the high speed, specifically, fusion of the toner to the surface of a carrier (scum formation), it has been tried to lower the surface energy of the carrier by coating the surface of the carrier with a resin (see JP-A-Showa-55-127569).